1. Field of the Invention
A catheter introduction syringe comprising a barrel and plunger combination wherein the plunger includes a centrally disposed passage having a valve assembly disposed therein to prevent the flow of fluid therethrough and permit the introduction of a catheter.
2. Description of the Prior Art
The art of introducing a catheter into a patient's body is difficult and often dangerous.
Commonly the central venous catheter placement is performed in the following manner:
(1) The patient is placed in Trendelenburg position to distend the thoracic veins if the internal jugular or subclavian veins are to be cannulated. The patient is placed in a flat supine position for cannulation of the femoral veins. PA1 (2) Using body landmarks, identified visually or by palpation, the vein is indentified by aspiration of blood. This is accomplished by gently aspirating a syringe as the needle is advanced. Once blood appears in the syringe presence of the needle within the lumen of the vein is confirmed. PA1 (3) In cannulation, catheter-over-needle catheter is advanced off the needle and down (or up) the vein, or; the syringe is removed from the needle and a catheter is threaded through the needle and into the vein, or; the syringe is removed from the needle and a guidewire is threaded through the needle and into the vein lumen. The needle is then removed leaving the catheter or guidewire in place. If the guidewire is used a catheter is threaded over the guidewire and down the lumen of the vein and the guidewire is removed.
In deep vein cannulation, the deep veins of the chest are exposed to the pressures created by respiration. During the inspiratory phase of respiration negative pressure is transmitted to the veins. In expiration positive pressure is transmitted to the veins. Therefore, if a subclavian or internal jugular vein is exposed to atmospheric pressure blood will pass from the vein during expiration while air will be pulled into the vein during inspiration. It is this latter situation which creates a potentially dangerous condition. If enough air enters the vein and goes to the heart it can result in an air embolus to the brain with the development of a stroke.
Numerous devices have been developed and used for catheter introduction.
For example, U.S. Pat. 4,274,408 discloses a syringe-type device for inserting a catheter guide wire into a blood vessel including a syringe in which the plunger has a central passage extending through it. A thin feeder tube including a central passge is slidably disposed in the central passage of the plunger. The plunger passage is normally blocked by a sphere received in a seat provided by a rubber tip on inner edge of the plunger body. The needle is inserted into the blood vessel and the plunger is then partially withdrawn to permit blood to be observed in the body of the syringe for verification of proper needle positioning. The thin feeder tube is then slid through the central passage past the sphere to eject the sphere to open the plunger passage. The thin feeder tube is further advanced to bring the inner end into contact with the end wall of the syringe. In this position, the central passage of the thin feeder tube is aligned and in communication with the needle lumen. A catheter guide wire may then be fed into the blood vessel by sliding it through the central passage of the thin feeder tube and the needle lumen. The device is then removed from the guide wire, and a beveled catheter is inserted over the guide wire in the usual manner.
U.S. Pat. Nos. 4,233,982; 4,245,635 and 4,261,357 also show catheter assemblies for intravenous use including a ball or spherical element to selectively operate as a vale sealing means.
U.S. Pat. No. 4,483,340 discloses a dilation catheter including a balloon element configured to be retracted by axial twisting following deflation.
U.S. Pat. No. 4,314,555 shows an intravascular catheter comprising a flexible catheter tube having the proximal end affixed to the distal end of a tubular hub of a catheter. A seal cap is connected to the catheter hub with a flexible tube disposed between the seal cap and catheter hub. The inner wall thereof closely abuts against the outer wall of a cannula which guides the catheter through the blood vessel. A location bar is fixed to a hub of the cannula and protrudes toward the distal end of the catheter. A stopper is mounted on the catheter hub to engage the distal end of the location bar.
U.S. Pat. No. 4,601,706 shows a central venous pressure catheter having a long flexible tube containing at least three channels or lumens. At the tip end of the catheter a balloon surrounds the tube and is inflatable via one of the channels. A distal port and a proximal port in the wall of the tube are located on either side of the balloon, and are connected to the other two channels respectively. The tip end of the catheter may be inserted through a jugular vein into a patient's superior cava vein near the heart. The balloon is inflated to partially obstruct the flow of blood and to increase the blood pressure at a site of surgery at the head or neck of a patient in the upright position to avoid air embolism as well as to prevent bleeding.
U.S. Pat. No. 3,215,141 discloses an apparatus for use in intravenous introduction of a fluid comprising an elongate hollow needle of uniform inner and outer diameter. One end of the needle is formed to provide a sharpened edge for making a vein puncture. A tubular needle holder is removably mounted upon the opposite end of the needle. A sleeve is fitted over the needle holder. A pliable sac is secured at one end to the outer surface of the sleeve and extends rearwardly therefrom. The opposite end of the sac is sealed. A flexible catheter is positioned within the sac with one end in the needle and extendable outwardly of thereof by manipulation through the sac. The uniform outer diameter of the the needle permits positioning flatly against a patient's body after withdrawal of the needle from the vein puncture and removal of the needle holder from the needle.
U.S. Pat. No. 4,517,979 shows a detachable balloon catheter comprising a sealing valve assembly having an elongated passageway extending therethrough. An inflatable balloon having a mouth portion is bonded to the periphery of the sealing valve assembly. A small diameter cannula having a distal end which extends through the passageway in the sealing valve assembly. The small diameter cannula includes a connector terminal on the proximal end which is adapted to be coupled to a source of fluid pressure. The sealing valve assembly includes a valve mechanism which permits the passage of the cannula through the passageway but prevents the flow of fluid through the passagewan when the cannula is removed.
U.S. Pat. No. 4,160,383 shows a unitary vent-valve assembly, useful in urological applications.
U.S. Pat. Nos. 2,936,756; 3,097,646; 3,308,820; 3,766,916; 3,853,127; 3,859,998; 4,029,104; 4,177,814; 4,200,096; 4,346,698; 4,424,833; 4,529,399; 4,606,347; 4,610,665 and France Patent No. 2,004,771 show various syringes or medical instruments employing elastomeric plugs or membranes as seals or valves in combination with syringes.
U.S. Pat. Nos. 3,739,778 and 3,851,647 disclose catheter introduction systems using removable plugs to selectively seal fluid or catheter channels.
U.S. Pat. Nos. 105,776; 2,711,734 and 4,356,823 disclose suction control in valve elements movable to selectively control the flow of fluid through a valve body.
U.S. Pat. Nos. 4,243,034 and 4,464,177 show clamping structures to seal or control the flow of fluid.
Additional examples of the prior art are shown in U.S. Pat. Nos. 3,040,743; 3,335,723; 3,920,013; 3,978,863; 4,448,195; 4,479,497 and Italy Patent No. 407,607.